Core drill



P 1932- H. c. JOHANSEN 1,878,241

CORE DRILL -Filed March 7. 1929 2 Sheets-Sheet 2 an improved core barrel.

Patented Sep 20, 1932 UNITED STATES PATENT OFFICE HARRY G. JOHANSEN, OF MICHIGAN CITY, INDIANA, ASSIGNOR IO SULLIVAN MACHINERY COMPANY, A CORPORATION OF MASSACHUSETTS CORE DRILL Application filed March 7,

This invention relates to core drills and more particularly to improved core barrels for such drills. I

An object of this invention is to provide Another object is to provide an improved core barrel of the double tube type. A further object is to provide' an improved core barrel having im-- proved fluid circulating means. Still another object is to provide improved fluid circulating means for a double tube core barrel whereby, when normal Circulation of fluid between the inner and outer barrels is interrupted or restricted, fluid may still flow through the barrel to the bottom of the drill hole. Yet 'another'object is to provide an improved double tube core barrel having improved fluid circulating means including a series ofpas'sages formed in the lower end of the inner core receiving tube above the core lifter whereby, when the flow of fluid between the inner and outer tubes is interrupted or restricted by the core lifter, fluid may still flow between the core and core lifter to the bottom of the drill hole. Another object is to provide an improvedcore barrel of the double tube type having improved guiding means for the inner tube for maintaining the latter centrally within the outer tube'and fluid passage means past said guiding means. These and other objects of this invention will, however, hereinafter more fully appear.

In the accompanying drawings there are shown for purposes of illustration two forms which the invention may assume in practice.

In these drawings,- i Fig. 1 is a central longitudinal sectional view through the upper end of a core barrel having the improved fluid circulating means embodied therein in one form.

Fig. 2 is a central longitudinal sectional view through the lower end ofthe improved core barrel. l

Fig. .3 is a transverse section taken 33 of Fig. 2.

Fig. 4 is a view similar to Fig. 2 showing the core lifter in its upper position.

Fig. 5 is a, view similar to 2 illustrating a modified form of the'invention.

on line '1929. Serial 1T0. 345,110.

Fig. 6 is a transverse section taken on line 66 of Fig. 5. In the illustrative form of the invention shown in Figs. 1 to 4 there is shown a core .edly connected at 6 to the lower end of the outer tube is a swell coupling 7 having an internally restricted passage therethrough and in turn threadedly connected at 8 to an annular core cutting bit-'9. Positioned within a chamber 10 formed within the head member 1 is an anti-friction bearing llheld in position by a bearing retainer or retainer sleeve 12 threadedly connected at 13 within the lower end ofthe head member 1. The head of a pin or bolt 14 engages the upper race of the antifriction bearing 11' and extends axially through an inner plug 15, the latter having an upwardly extending sleeve portion 16 having a sliding fit within the bearing retainer 12. A nut.16 threadedlyconnected to the lower end of the bolt 14 engages the bottom surface ofthe inner plug and maintains the partsin assembled relation. Threadedly conngeted at 17 to the inner plug-15 is an'inner core receiving barrel or tube 18 having secured there- .toat its lower end'at 19 an inner tube extension 20. The inner core receiving tube is arranged concentricallv within the outer tube and is rotatable relative thereto. The annular bit 9 has a central core passage 21 and a conical bore 22 in which a usual split spring core lifter 23 is arranged. The lower end of the inner tube extension 20 forms an abutextension ;the fluid flowing through an enlarged chamber 27 formed in the swell coupling 7 and through the bit to the bottom of the drill hole. In this instance the swell coupling 7 isprovided with a plurality of inwardly projecting ribs 28 and theseribs guide and maintain central the lower end of the inner tube, and fluid passages are formed- I shown in Fig. 5 the guide ribs 28 on the swell coupling? are omitted and the inner tube extension 31 has formed externally thereon projecting ribs 32 which serve as guidesfor the lower end of the inner core receiving tube. Fluid assages 33 are formed between the ribs 32 an a plurality of openings 34, are formed between the ribs and connecting these passages with the interior of the inner tube. Otherwise this form of the invention is the same as the form described above. It will be noted that in both forms of the invention the inner core receiving tube may be of the swivel type as shown in Fig. 1 or of the rigid type wherein the innercore receiving tube is held against rotation relative to the outer tube.

In the use of the improved core barrel it will be noted that during the drillin operation the core (indicated at C in Fig. 4 cut by the bit 9 passes through the core lifter 23 into the inner core receiving tube 18. During the normal operation fluid flows through the rod line into the chamber 24 downwardly through the passages 25 and through the space between the inner and outer tubes, past the reduced portion 26 on the inner tube extension 20 into the enlarged chamber 27 iethe swell coupling 7, through the passages betwe the ribs 28, and past the core lifter 23 and th ugh the core passage 21 in the bit to the bottom of the drill hole. During the drilling operation the core lifter 23 tends to cling to the core and is forced upwardly against the bottom of the inner tube extension 20 as shown in Fig. 4, partially restricting the fluid flowbetween the tubes and frequently packing dirt in around the lifter and in the space between the tubes, thereby cutting off or restricting fluid flow between the tubes past the exterior of the core lifter to the bottom of the bit. Fluid then flows from between the inner and outer tubes through the openings 29 in the lower end of the inner tube into the interior of the latter, the fluid then passing between the core lifter 23 and core C and through the bit 9 to the bottom of the hole. If the openings 29 in the lower end of the inner tube were not present a considerable pressure would build up in the space between the inner and outer tubes, forcing the core lifter 23 downwardly, contracting the same against the core and practically cutting ofl the supply of fluid to the bit, and, due to the engagement of the core lifter with the core, causing wear of the internal gripping surface of the core lifter, rendering the same practically useless. By providing the openings in the inner tube at its lower end, this is avoided, the fluid flowing freely past the core lifter even when the flow between the lower ends of the tube is restricted or completely out off. In the form of the invention shown in Figs. 5 and 6 the operation is the same as that described above with the exception that the fluid flows between the inner and outer tubes through the passages between the projecting guide ribs 32 on the lower end of the inner tube extension and thence past the core lifter and through the passage in the bit to the bottom of the hole.

As a result of this invention it will be noted that an improved core barrel is provided having improved fluid circulating means whereby, even when normal fluid circulation is interrupted, fluid mav still flow to the bottom of the hole. It will further be noted that an improved core barrel of the double tube type is provided having improved guiding means for the inner tube and improved fluid passage means in the inner tube whereby, when fluid' flow, through the space between the tubes is interrupted, fluid may flow through these passages interiorly through the inner tube and past the core lifter to the bottom of the hole. It will further be evident that improved fluid circulating means is provided which may be applied to a double tube core barrel of standard construction with a minimum of change. These and other uses and advantages of this invention will, however, be clearly apparent to those skilled in the art.

While there is in this application specifically described two forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims. I

WhatI claim as new and desire to secure by Letters Patent is:

1. A core barrel comprising an outer tube, an inner core receiving tube arranged within and spaced from said outer tube and terminating within said outer tube, an annular vcore cutting bit carried by said outer tube,

said inner tube receiving the core cut by said bit, means for venting the upper end of the inner tube, and means for conducting fluid through the space between the inner and outer tubes and through the bit to the bottom .of the drill hole including fluid conducting passages in said inner tube for connecting the space between said tubes with the interior of the inner tube.

2. A core barrel comprising aniouter tube,

forward face of said bit, and means for conducting fluid through the space between the inner and outer tubesand through the bit to the bottom of.the hole including a series of openings formed within the lower end of the inner tube and connecting the space betwteen the tubes with the interior of the inner tu e.

3. A core barrel comprising an outer tube, an annular core cutting bit carried thereby, a core lifter carried by' said bit, an inner core receiving tube arranged concentrically within and spaced from said outer tube and having its lower end terminating above the core lifter, and means for conducting fluid through the space between the inner and outer tubes past the core lifter and through the bit to the bottom of the drill hole including passages formed in the lower end of said inner tube and connecting the space between the tubes with the interior of said inner tube.

4. A core barrel comprising an outer tube, an annular core cutting bit carried thereby, an inner tube receiving the core cut by said bit and arranged concentrically within said outer tube and terminating within said outer tube at ,the rear of the forwardface of said bit, and means for conductingfl uid between said tubes and through the bit to. the bottom of the drill hole including radial passages formed in the lower end'of said inner tube above said bit.

5. A core barrel comprising an outer tube, an annular core'cutting bit carried thereby, a core lifter carried within said, bit, an inner core receivingtube arranged concentrically within and spacedfrqm said outer tube, and means for conductin g fluid through the space between the inner and outer tubes and through the bit to the bottom of the drill hole including means for conducting fluid from the space between the tubes into the interior of the' inner tube when normal flow space between. the tubes and through the bit to the bottom of the drill hole and including by-pas s means for conducting fluid through the bit when normal flow therethr'ough is interru ted.

7. core barrel comprising an outer tube, an annular core cutting bit carried thereby, an inner tube receiving the core cut by said bit and arranged concentrically within and spaced from said outer tube, said inner tube terminating within said outer tube at the rear of the forward face of said bit, means for venting the upper end of the inner tube, and 'meansfor conducting fluid through the space between the tubes and through the bit to the bottom of the drill hole and including by-pass passages in said inner tube for conducting fluid through the bit when normal flow through the space between the tubes is interrupted.

8. A core barrel comprising ah outer tube having an internally restricted portion between'its ends, an annular core cutting bit secured to said outer tube, an inner tube receiving the core cut by said bit and arranged concentrically within and spaced from said outer tube and having an externally reduced portion coextensive with said restricted outer tube portion, said inner tubeterminating within said outer tube atithe rear of the forward face of said bit, and means for conduct-- ing fluid through the space between the tubes and past said restricted portion through the bit to the bottom of the drill hole and including radial passages formed in the lower end of said innertube below said reduced portion.

9. A core barrel comprising an outer tube, a head member secured thereto, an annular core cut-ting bit secured to said outer tube, an inner tube receiving the core out by said bit and arranged concentrically within and spaced from said outer tube and freely rotatably supported by said head member for rotation relative to said outer tube, and means for conducting fluid through the space between the tubes and through the bit to the I bottom of the drill hole including radial passages formed in the lower end of said inner. tube.

10. A core barrel comprising an outer tube, an annular core cutting bit secured thereto, an inner core receiving tubearranged within said outer tube and having a lower free end,

one of said tubes having an internally restricted portion and the other having an externally reduced portion, coextensive with said restricted portion, and means for conducting fluid through the space between the tubes and past said restricted portion and the lower free end of said inner tube to the bot tom of the bit and including radial passages formed in the lower end of said inner tube belowsaidrestricted portion.

11. A core barrel comprising an outer tube, an annular core cutting bit carried thereby, an inner core receiving tube arranged concentrically within and freely rotatable relative to said outer tubeand adapted to remain stationary while said outer tube rotates, one of said tubes having an internally restricted portion between its ends while the other has an externally reduced portion coextensive with said restricted portion, and means for conducting fluid through the space between the tubes and past said restricted portion and through the core-surrounding opening of the bit to the bottom of the drill hole, said outer tube having an enlarged chamber therein within which the lower end of said inner tube projects.

12. A core barrelcomprising an outer tube, an annular core cutting bit, aicoupling connecting said tube and bit and forming a restricted opening in the barrel of less diameter than the main bore of said tube, and an inner core receiving tube arranged concen-.

trically within said outer tube and freely rotatable relative thereto, said inner tube having an externally reduced portion coextensive with the restricted portion of said coupling.-

In testimony whereof I aflix my signature.

HARRY C. J OHANSEN. 

